Answer: M = 2.08 M
Explanation: Molarity is expressed as the number of moles per unit volume in liters. First convert the mass of HCl to moles using its molar mass. Then substitute the variables to the formula for molarity.
75.00 g HCl x 1 mole HCl / 36 g HCl
= 2.08 moles HCl
For Molarity.
M = n / L
= 2.08 moles HCl / 1.000 L
= 2.08 M
Molality is defined as 1 mole of a solute in 1 kg of solvent.
Molality=

Number of moles of solute, n=

Given mass of the nitrobenzene=0.2 g
Molar mass of the substance= 123.06 g mol⁻¹
Number of moles of nitrobenzene,

Number of moles of nitrobenzene, n= 0.0016 mol
Mass of 10.9 g of naphthalene in kg=0.0109

Molality= 0.146 m
An element with 8 valence electrons is Neon (Ne).
Ps: Any element under group 18 has 8 valence electrons except for Helium (He).
There are 1.2 hr would this current have to be applied to plate out 7. 20 g of iron .
Calculation ,
Given ; Current ( I ) = 5. 68 A
In
, the valancy of Fe is +2 .
2 moles of
are required for the decomposition of 1 mole of Fe .
7. 20 g of Fe in moles = 7. 20 g /55.845 g/mol =0.12 mole
x moles of
are required for the decomposition of 0.128 mole of Fe .
moles of
are required = 0.256 moles
Charge on 1 mole of
= 96500 C
Charge on 0.256 mole of
= 24704 C
Current ( I )= Q/t
t =Q / I = 24704 C/5. 68 A = 4349 sec = 1.2 hr
Therefore , there are 1.2 hr would this current have to be applied to plate out 7. 20 g of iron .
To learn more about iron
brainly.com/question/18500540
#SPJ4
The total mass is 10.57+6.96=17.53 g.
So, the percent by mass of magnesium is (10.57)/(17.53) * 100 = <u>60.3%</u>
<u />
The percent by mass of oxygen is (6.96)/(17.53) * 100 = <u>39.7%</u>